Prior to the present invention, a deformable plastic insert, having a pocket containing a spring metal clip, was forced into an irregular shaped slot on the edge of a piece of sheet metal in the form of a cover. The irregularities in the slot provided the retention capability and the spring clip co-acted with a pin on a mating piece of sheet metal. To help disengage one piece of sheet metal from the other, handles were welded to the sheet metal containing the insert. However, when the cover was removed from the mating portion of the assembly, the pulling action sometimes caused the sheet metal to bow thereby allowing the sheet metal slot to distort enough whereby the deformable plastic would disengage from the sheet metal cover and remain engaged with the mating pin.
The accidental loss of the insert has been solved by the present invention in using locking extensions which can be forced through openings on either side of the slot and due to the high shear resistance of the protrusions (right angle disengagement forces), prevent accidental disengagement of the spring retaining pocket upon disengagement of the latch. By making the latch mechanism in an L-shape, a handle is provided to eliminate the added labor and material costs of welding handles to the sheet metal cover.
It is thus an object of the present invention to provide an improved latch mechanism which will not accidentally disengage when the sheet metal is distorted and which provides a built-in handle to assist in disengaging the latch.